a3 front sight post

[ssgross]

up next on my list...this A3.
I'll start by saying it shoots great...but zeroing requires maxing out left windage because the front sight is obviously pointing to 11 o'clock or so.
The blade is not bent.
The witness mark on the receiver is perfectly aligned to the one on the barrel.
When zeroed, a witness mark on the original rear sight housing (yolk holder? whatever) lines up with a corresponding witness mark on the receiver bridge.
My conclusion therefore is that this barrel was made this way - and it is annoying as a left handed shooter to have the rear sight assembly pushed off-center all the way over by 1/4 inch or more.
During manufacturing, was the timing mark on the barrel applied before or after it was put on the receiver? If I unscrew the barrel 1/12 of a turn (maybe a bit less) will this create excessive headspace? Right now headspace is tight, bold barely turns on my Forrester no-go.
Attachment 113869Attachment 113868Attachment 113867Attachment 113866
It was hard to get a good picture that shows what alignment the eye sees. Third pic falsely looks like the blade might be bent only cause the camera lens was off center a bit.

Information

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[Doco overboard]

I would start simply by making sure the key for the front sight band is in place.
If for some reason the key was not installed or the wrong size, fell out or was lost, the band may have just become slightly rotated.

[browningautorifle]

the key was not installed

That's what it looks like. Check out the front end first.

[ssgross]

There certainly is a key in there, me thinks
Attachment 113887
The key or keyway could be damaged, or the key too small. I'll give it soak again. I tried to get the pin started - right to left (looking from behind the rifle) - with a regular punch and lots of small taps. I didn't want to beat on it and break/bend my punch. I think I need to support the blade with a block of wood, and give it a really big fing whack with a small nail set to get it started. The pin is tapered right? and right to left is the correct exit?
I saw chuck's method of cutting it off - but will try to save it first.

[ssgross]

Yahtzee that was easy! Got the pin started moving right to left with a 1/32 nail set and a very big hammer. I supported the sight with wood door shims to protect it. When I switched to a regular punch, it wouldn't budge. Tried hundreds of small taps - tried to let the vibrations work some more kroil around it. punch started to bend.
Hmmm. I took a small hand torch and lightly touched around the the pin for a few seconds - just a bit of warmth - I could still touch it without burning my finger. punch snapped midway up the tip...but the shortened punch then started to move the pin right out!
Muzzle against a carpet on the concrete floor, and a piece of hardwood dowel behind it. The sight collar started to move after a few blows.

Now the diagnosis...nothing wrong with the key (key came out after scrubbing with kroil and pulling with needle nose). Either the keyway was cut wrong, or the witness mark on the barrel was off, or both - this barrel was over timed quite a bit. I used a hex wrench to make sure my level was on the flat of the milled part.
Attachment 113904Attachment 113902Attachment 113903

[ssgross]

Just to convince myself I'm not going crazy, the marks do match up. Were the barrels marked when manufactured, or when assembled? I thought since all the replacement barrels I've seen already have witness marks on them they were pre-marked.
Attachment 113905

[Doco overboard]

Just to convince myself I'm not going crazy, the marks do match up. Were the barrels marked when manufactured, or when assembled? I thought since all the replacement barrels I've seen already have witness marks on them they were pre-marked.
Attachment 113905

Just a thought, when you peer into the breech, does the barrel extractor cut seem to be off as much off as the front site is rotated?
I'm just going off the pictures supplied earlier in the thread, the front site band appeared to have a pretty good lean to it.

One time I had a replacement barrel either for a M17 or P14 that had the index mark off just a touch more than the index mark was wide. Luckily the manufacturer had cut the extractor slot generous enough that I could remedy the problem with a slight turn to he barrel.

The index mark on the barrel was just proud of the mark on the receiver but not past it much more than the width of the barrel mark so the movement was a couple thou at best.

[ssgross]

does the barrel extractor cut seem to be off as much off as the front site is rotated

Just took a look down the action. If I line my eye up to look right down the raceway for the right lugs down to the extractor groove...it looks to be off slightly in the same direction? could be bias too as well now that I confirmed the sight was off.
I also think now that I have the front sight off that my pics, not being perfectly aligned and level, exaggerated the misalignment. I think/hope it will end up being off by about the width of the index marks. You bring up a good point with the alignment of the extractor groove that I hadn't considered yet. Guess we'll have to wait to find that out too!

[browningautorifle]

the width of the barrel mark

That would be all the barrel would need to move so maybe not even take it off completely.

[ArtPahl]

OK, here's a thought: Why not file a little off the upper side of the sight key and then shim the other side until the sight lines up? Seems a lot less hassle and risk than trying to twist the barrel tighter (if you even can!). There's a good chance the barrel or receiver will get marred up, where as if you file the sight key.....what's the worst that can happen?